c) a^2 – 2ab – 4a + 8b
c) a2 – 2ab – 4a + 8b
c) a2 – 2ab – 4a + 8b
= (a2 – 2ab) – (4a ‒ 8b)
= a(a ‒ 2b) ‒ 4(a ‒ 2b)
= (a ‒ 2b)(a ‒ 4).